Phonograph recorder



Aug. 21, 1923. 1,455,764-

N. H. HOLLAND PHONOGRAPH RECORDER Filed Nov. 6, 1920 Wpzzm 7 PatentedAug. 21, 1323.

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NEWMAN n. HOLLAND, or WEST ORANGE, NEW JERSEY, assxsnon TO NEW JERSEYPATENT comm, or WEST ORANGE, NEW JERSEY, A CORPORATION on NEW JERSEY.

rnzonosnarn RECORDER.

Application filed November 6, 1920. Serial 1%. 422,122]

T 0 all whom it may comer n.

Be it known that I, NEWMAN H. HOLLAND,

a subject of the King of Great Britain, and a resident of West Orange,in the county of Essex and State of New Jersey, have invented certainnew and useful Improvements in Phonograph Recorders, of which thefollowing is a description.

My invention relates to phonograph recorders and more particularlyphonograph recorders ofthe floating-weight type.

It is highly essential in phonograph recorders in order to obtain afaithful record of the matter to be recorded, for the construction andarrangement to be such that the recording stylus will engage the. recordtablet with a pressure not appreciably greater or less than-a certainpredetermined amount. There are certain advantages which would obviouslyresult from the use of a recorder of the floating-weight type, such asrendering it possible during the recording operation to support thediaphragm or vibratory means against movement towards and awav from therecord tablet, and, especially in the case of an electro-magnetrecorder, to maintain the diaphragm or vibratory means in fixed relationto the means, such as the electro-magnet, for efi'ecting vibrationthereof. Constructions heretofore suggested for phonograph recorders ofthe floating-weight type are impracticable, for in these constructionsduring the recording operation there is either insuflicient tension inthe con' nection between the stylus and the diaphragm to preventlooseness and rattling-in such connection, or the pressure with whichthe stylus engages the record, tablet is far too great.

One of Another object of my invention resides' in the provision of afloating-weight recorder of this character wherein the vibrationsimparted to the recording stylus cor- .respond in amplitude to thevibrations of the central portion of the diaphragm.

the principal objects of my inven-' tion is to provide an improvedconstruction the latter.

Other objects and features of my invention will be hereinafter morespecifically described and claimed.

In order that my invention may be more clearly understood, attention isdirected to the drawing accompanying and forming a part of thisspecification and in which the single figure is a fragmental view inelevation, partly in section, of a phonograph illustrating one form ofrecorder embodying my invention, in operative position with respect tothe record tablet.

Referring to the drawing, reference oharactor 1 represents "acylindrical record tablet such as is usually employed on'busines'sphonographs or dictating machines, and 2 the traveling arm or carriagewhich in the operation of the phonograph is fed rectilincarly across thetablet 1. The carriage 2-constitutes a support for the sound box casing3 of the recorder, being provided with an opening in which said casingis removably secured in any suitable manner. A metallic diaphragm 4 issuitably secured as by means of'a ring 5 within the casing 3 so astoclose the open end of the latter. In the form of recorder shown, thediaphragm 4 is adapted to be vibrated by means of an electro-magnet 6suitably mounted in 'a fixed position within the casing 3 and theterminals of which are respectively connected to-binding posts 7 and 8,the latter extending through and being'insulated from the upper end wallof the casing 3. The binding posts 7 and 8 are adapted to beelectrically connected to a telephonic transmitter, not shown. Y

Reference character 9 represents a floating weight preferably having oneend pivotally supported at 10 between a pair of lugs 11, only one ofwhich is shown, pro-- jecting downwardly from the sound box casing 3,and provided at its other end with a pin 12 whichis embraced by .akeeper 13 secured to the sound box casing 3 and extending downwardlytherefrom at a point diametrically opposite the lugs 11. A stylus lever14 is pivotally mounted intermediate its ends at 15 on thefloatlngweight 9 within an opening 16 provided in The stylus lever 14has a recording stylus 17 mounted in one end there of and its other endis connected as by means of a link 18 with a button 19 fixed to thediaphragm 4;.

' The arms ofthe stylus lever 14 are of unequal length, the shorter armbeing connected, as by means of the link 18 and button 19, to thediaphragm 4 and the longer. arm carrying the stylus 17. It will,therefore, be apparent that the tension in the connection between thediaphragm 4 and the lever 14 will be greater than if the lever werepivoted midway between its ends as is customary, and eater than thepressure with which the sty us'17 engages the record tablet 1. Thistension in the connection between the stylus lever and the diaphragm,and the pressure with which the stylus engages the recordtablet, will bedependent on the mass of the floating-weight 9, the point where thestylus lever 14 is pivoted on the floatingweight, and the relativelengths of the two arms of the stylus lever. In the constructionshown'the longer arm of the stylus lever 14 is substantially twice thelength of the shorter arm and, therefore, the tension in the connection,which includes link 18, be-

tween the diaphragm and the stylus lever 14, will be equal tosubstantially twice the pres sure with which the stylus 17 engages the,

tablet 1. The mass of the floating-weight 9 'and the point 15 thereon atwhich the lever 14 is pivotally mounted, are so chosen that the stylus17 engages the tablet 1, when the recorder is'in operative posit-ion asshown, with exactly the proper degree of pressure to properly record onthe tablet. Under these conditions it is found that the tension in theconnection between the diaphragm and the stylus lever is entirelysuflicient to v prevent all looseness, rattling, etc. in such connectionduring the recording operation, with the result that a faithful recordis produced. i

It is also important-while obtaining ,the results-just described,toimpart to the recording stylus vibrations corresponding in amplitudeto the vibrations of the diaphragm at the center thereof. This Iaccomplish by connecting the shorter arm of the stylus lever 14 to thediaphragm 4 eccentrically thereof, as'by means of ink 18 and button '19,so that the distance between the center of the diaphragm and the int atwhich the stylus lever is connecte' thereto and the radius of thediaphragm, are in the same ratio as the lengths of the arms of lever 14.

'Thus where the shorter arm of the lever 14 is one-half the length ofthe longer arm thereof, as shown, the shorter arm of the lever isconnected to the diaphragm at a point midway between the center and theedge thereof.

It is to be understood that in the embodi ment illustrated, the mass ofthe floatingweight, the point on the floatin weight at which the styluslever is pivote the relative lengths of the arms of the stylus lever andthe point at which the diaphragm is connected to the stylus lever aresubject to wide variation, and that many other modifications may be madein the form and arrangement of the parts without departure from thespirit of my invention and the scope of the appended claims.

Having now described my invention, what I claim as new and desire toprotect by Letters Patent, is as follows: 1. A phonograph recordercomprising a diaphragm, a member movable relative "thereto, a styluslever pivotally mounted intermediate its ends on said member and havingarms of unequal length, the shorter arm of said lever'being connected tosaid diaphragm eccentrically thereof, and a stylus carried by the longerarm of said lever, substantially as described. A

2. A phonograph recorder comprising a' diaphragm, a stylus leverpivotally mounted intermediate its ends and havin arms of unequallength, the pivot on whic said lever is mounted being movable relativeto the diaphragm, the shorter arm of said lever being connected to saiddiaphragm eccentrically thereof, and a stylus carried by the longer armof said lever, the distance between the center of the diaphragm and thepoint thereof to which the stylus lever is connected and the length ofthe radius of the diaphragm being in substantially the same ratio as theI length of the shorter arm of the stylus lever and the length of thelonger arm thereof, substantially as described.

3. A phonograph recorder comprising a diaphragm, a stylus leverpivotally mounted intermediate its ends and having arms of unequallength, the pivot on which said lever is mounted being movable relativeto the dia phragm, the shorter arm of said lever being substantiallyhalf the length of the longer arm thereof and being connected to thediaphragm at a point substantially midway between the center and theedge thereof, and

a stylus carried by the longer arm of said. lever, substantially asdescribed.

4. A phonograph recorder comprising a diaphragm, a stylus leverpivotally, mounted intermediatevits ends and having arms ofunequal'length, the shorter arm of said lever being connected to saiddiaphragm eccentrically thereof, and 'a stylus carried bythe longer armof said lever, substantially as described. v

This specification signed this third day of November, 1920.

' NEVVMAN- HOLLAND.

